"Create a dark, atmospheric background image for a Facebook theme page

"Create a dark, atmospheric background image for a Facebook theme page: "SHUDOIN DOJO". The overall theme should be in black and gray tones, featuring dynamic, swirling smoke elements like a dragon to create depth and a mysterious ambiance. The smoke should flow and blend seamlessly across the image, with varying shades of gray to add texture and movement. No central figures; focus on the abstract interplay of light and shadow within the smoke to evoke a powerful, intense mood. The background should be versatile enough to overlay text or logos if needed."